Project Summary Weight management and sedentary lifestyles are of growing concern for public health in the United States with nearly 32% of children ages 2-19 classified as either overweight or obese. Further, over 70% of children fail to meet recommendations for moderate to vigorous physical activity. Walking and playing with pet dogs, however, may be a protective factor against sedentary lifestyles by encouraging walking and other physical activity. Pet dogs may be particularly important in increasing physical activity given that 51% of homes with children have pet dogs. Our long-term goal is to evaluate a causal model of canines influencing children?s physical activity and evaluate intervention and prevention efforts to increase physical activity in children. Our objective here, is to use objective accelerometer measures of physical activity to evaluate the effect of pet dogs on children?s overall physical activity (PA) and moderate to vigorous physical activity (MVPA). Using continuously worn accelerometers on children with and without dogs we will evaluate whether pet owners engage in more PA. One innovation of the proposed study is to use an accelerometer on the dog, allowing for periods of synchronized activity, such as walking the dog or playing with the dog, to be objectively quantified with a novel measure of Dog Associated PA. The specific aims of this project are to (1) determine whether a pet dog in the home is associated with physical activity in children (compared to children without a pet dog), (2) identify the amount of physical activity a child engages in that is directly related to the dog (Dog Associated PA), and (3) evaluate the association between child attachment to their pet dog and Dog Associated PA. The outcomes of this project will evaluate the potential of pets to increase physical activity in children and develop needed objective measures for studies evaluating canines? impacts on owners? physical activity.